Answer:
(2) the same kingdom, but different species
Step-by-step explanation:
Living organisms can be classified in five kingdoms: Monera, Protista, Fungi, Plantae, and Animalia.
Dogs and cats are classified in the Animalia kingdom, as they are composed of cells that are eukaryotic, have means for locomotion, and acquire nutrients by ingestion.
However they are classified as different species because they do not mate with each other.